Hot Hamburger Sandwich - Cooking like a Boss

Traditional Canadian comfort food. It's a burger on top of a slice of bread covered in gravy. Much nicer than it deserves to be! Serve with garden peas and chips.

5 medium onions	dice	fry in burger pan until golden	fry until mushrooms golden	melt	stir in	stir in	season	return burgers to pan	cover and simmer until cooked through	top
oil
10cups 2.37l 2366ml 4.16pint 158tbsp 473tsp mushrooms	slice
5tbsp 0.075l 75ml 15tsp 0.317cup 0.132pint butter
5tbsp 0.075l 75ml 15tsp 0.317cup 0.132pint flour
937 ¹⁄₂ml ¹⁵⁄₁₆l 62 ¹⁄₂tbsp 187 ¹⁄₂tsp 3.96cup 1.65pint beef broth
2 ¹⁄₂tbsp 0.037l 37 ¹⁄₂ml 7 ¹⁄₂tsp 0.159cup 0.066pint marmite
burgers
1250g 1 ¹⁄₄kg 2.76lb 44.1oz minced beef	mix	form into 10 patties	brown	remove to plate
2 ¹⁄₂tbsp 0.037l 37 ¹⁄₂ml 7 ¹⁄₂tsp 0.159cup 0.066pint worcestershire sauce
2 ¹⁄₂tbsp 0.037l 37 ¹⁄₂ml 7 ¹⁄₂tsp 0.159cup 0.066pint garlic powder
salt
pepper
2 ¹⁄₂tbsp 0.037l 37 ¹⁄₂ml 7 ¹⁄₂tsp 0.159cup 0.066pint onion powder
2 ¹⁄₂ egg
oil
10 slices of white bread